uORB: generate ORBTypeMap and example usage (uORB::Publication2)

msg/templates/uorb/msg.h.em

@@ -70,6 +70,10 @@ topic_name = spec.short_name
 
 #include <uORB/uORB.h>
 
+#ifdef __cplusplus
+#include <uORB/topics/uORBTopics.hpp>
+#endif
+
 @##############################
 @# Includes for dependencies
 @##############################
@@ -135,5 +139,11 @@ ORB_DECLARE(@multi_topic);
 @[end for]
 
 #ifdef __cplusplus
+@[for multi_topic in topics]@
+template<> struct ORBTypeMap<ORB_ID::@multi_topic> {
+    using type = @(uorb_struct);
+};
+@[end for]
+
 void print_message(const @uorb_struct& message);
 #endif

msg/templates/uorb/uORBTopics.hpp.em

@@ -73,4 +73,6 @@ enum class ORB_ID : uint8_t {
 	INVALID
 };
 
+template<ORB_ID> struct ORBTypeMap;
+
 const struct orb_metadata *get_orb_meta(ORB_ID id);